The moral circle: who matters, what matters, and why

Abstract

Expanding the moral circle requires incorporating invertebrates and artificial intelligence systems into contemporary ethical and legal frameworks. Criteria for moral standing—such as sentience, agency, or the capacity for welfare—are not exclusive to the human species or carbon-based substrates. Given persistent scientific and philosophical uncertainty regarding the nature of consciousness, the risk principle dictates that any entity with a non-negligible probability of being morally significant merits ethical consideration. Human activity in the Anthropocene generates large-scale, indirect impacts that affect quadrillions of current and future individuals, necessitating a transition away from human exceptionalism. A pluralistic approach to harm reduction recognizes that human and nonhuman interests are deeply interconnected, particularly concerning global risks like climate change and technological development. Ethical responsibility involves not only avoiding direct harm but also cultivating institutional and social structures that support multispecies justice. As technological and economic capacities increase, so does the obligation to mitigate risks to distant and diverse populations. This entails moving toward systems of governance that prioritize the interests of all potential moral patients regardless of their proximity in space, time, or biology, thereby fostering a more inclusive global and cosmic ethical trajectory. – AI-generated abstract.